You may scoff, but there is a strong scientific reasoning behind this. Once we terraform the moon and have a society living up there, pretty soon that society is going to collapse. By hiding these scientific treasures for them to find in the distant future, we can potentially kick-start a resurgent scientific age and save ourselves a lot of trial and error.

We should also think about sticking some dinosaur fossils up there as well, just to get some heated religious/evolutionary debates underway.

Moon orbit is no different from earth orbit; all you have to do is fire an engine to slow down and you will crash into it. Although hitting exactly the right spot - as well is getting into the right orbit to begin with - is rocket science, crashing into it in priciple decidedly is not; gravity will do that for you if you give it a chance.

Your stone and string example is completely irrelevant; unless you do it very far away from the surfice of the earth, of course!

Luna 1 [wikipedia.org] was intended to crash into the Moon but failed. The Soviet scientists then renamed their little probe "Mechta", meaning "The Dream". The dream being the dream of exporting the rest of space.

The purpose of the experiment was
1) To try the ION-engine
2) To get dust from the moon in the atmosphere for analysis

I think (1) justified it. The satellite had already done a good job (collecting information) for several years. Instead of letting it remain in the universe with all the other debris we put there, scientists decided to do something useful while scrapping it.

> Instead of letting it remain in the universe with all the other debris

You're missing something. Due to the gravity disturbances of the earth and the sun, the orbit decays naturally. So it was bound to end up crashing on the moon. They had used up all but a few grams of the xenon gas, and the last maneuvres were done using the hydrazine thrusters (used for pointing and gyro offloading). They just set a favorable time and place of impact. Hmm, the "just" is maybe a bit misplaced; they did a great job.

This can only be seen as great news for the ion drive. SMART-1 spiralled around the Moon exactly as planned, and was targetted at the Sea of Excellence with utmost precision. Perhaps we'll be seeing more probes with tiny amounts of fuel in the near future...?

I downloaded the animated GIF and pulled it into ImageJ (http://rsb.info.nih.gov/ij/index.html). My intent was to examine the frame immediately after the flare (which was frame 11) for any evidence of lingering heat.

Yeah, kinda reminds me of those lamers who strut around with their dicks stiff in the air talking about the great things "we" did at "our" university... just... someone other than him that actually did it... but hey, he can be proud of it, right? Even though, you know, he didn't do it.

Was there a good chance that it would miss? Was there the possibility of an "unsuccessful" crash?

Ah, you must've read THHGTTG (shameless paste follows):

There is an art, it says, or rather, a knack to flying. The knack lies in learning how to throw yourself at the ground and miss. Pick a nice day, [The Hitchhiker's Guide to the Galaxy] suggests, and try it.

The first part is easy. All it requires is simply the ability to throw yourself forward with all your weight, and the willingness not to mind that it's going to hurt.

That is, it's going to hurt if you fail to miss the ground. Most people fail to miss the ground, and if they are really trying properly, the likelihood is that they will fail to miss it fairly hard.

Clearly, it is the second part, the missing, which presents the difficulties.

The dust is certainly interesting to study, but I should say the ion propulsion engine on board is also a very interesting development. Maybe further development/use of this engine will lead to faster/more frequent/lower-cost space missions than now.
Good thing NASA is slating ion propulsion for future unmanned missions... it would be interesting if Orion (or whatever that thing is called) can use ion propulsion once it clears Earth's gravitational force.

The ion engine is good for efficiency, but very bad for any human exploration. It takes years to get the spacecraft up to speed (and SMART-1 didn't have any fuel for landing). The Moon is only a few days travel using chemical rockets, so I don't think Orion could get much use from it. Sending payloads in advance may be worth doing, especially when going to Mars and beyond.

SMART-1 uses Hall effect thrusters [wikipedia.org]. These have been flown on dozens of Russian spacecraft over the past thirty years. So, I wouldn't neccessarily say that SMART-1 is such an interesting development. However, SMART-1 is the first non-Russian space vehicle to use such an engine. This in itself is very interesting, considering that the first ion thruster (based on a different principle, though) was invented in the US back in the 60s. I wonder why such delay, considering all the advantages offered by ion thrust

Well, we showed the Commies, didn't we? Not only did we smack into the moon, but we've smacked into comets, we've smacked into Mars, we've smacked into the earth, we're getting to good at smacking that we smack into things without having to bother planning to do it. NASA is the worldwide leader at taking a few hundred million dollars and turning it into a giant crater on your celestial body of choice.

So "SMART-1 orbited the Moon more than 2000 times and mapped the mineralogy of the lunar surface" before it was successfully crashed into the surface. Scientists expect the ejecta from the crash to settle over up to a square kilometer of the impact site. Do we now need to send up another probe to remap the surface which was disturbed?

Putting a link to a 3.5 meg GIF, on slashdot's front page. Yeah. For those who didn't get a chance to watch it, at 5:42:15:93 there was a round white flash over a grey rectangle scattered with black dots.

Could somebody explain to me what those black dots are in the animation? Also, does anybody else think that the probe is visible a frame or two before impact in the upper left corner? or is that just some anomaly?

Here's the BBC story [bbc.co.uk] on this event. What I found particularly nice about this report was that in a "mainstream" news outlet there was no dumbing-down of the technology, such as the ion drive.

I'm reminded of K240 with its poorly orchestrated ship to ship battles and all you see are random explosions because you were to skint to defend your asteroids with anything other than scout ships with x10 shields. But without the sound.

Are we under attack? Moon is soveign US territory (we planted the flag first -- end of story). Is this the first wave of attack? Are we not going to respond? Anyone know the scoop? Is Christiane Amanpour on her way to the moon?

I'm back from the computational astrobiology summer school in Honolulu and we were lectured by Karen Meech who was on the scientific comity for Deep Impact and in charge of all Earth based observations. Despite the catchy depiction of the mission as a space demolition derby its a perfectly valid way to study stuff out there.

By smaching stuff hard enough they can vaporize matter and use Earth based spectrometers to get a really detailed description of the content. For those not into astronomy, when you split the light from a neon light, you see distinct rays, not a continuous spectrum. You can identify the gas in the tube by just looking at its rays, argon lights are different from neon and so on. When you vaporize any kind of matter you get a spectrum. You can tell whats in the sample by looking at emission or absorbsion rays depending on wether your sample is the light source or a filter. There is a catch, from Earth you can only tell the elements (and sometimes molecules) that have rays in the transparency windows of our atmosphere,

The good side of the Deep Impact kind of missions is that you can study an object on the "cheap". You just send something to be smashed and the science package is already on earth. No need to build a high price mass spectrometer and to find a way to land it without crashing. In the case of Deep Impact, you don't even need to accelerate the impactor, the comet already has all the momentum required to cause vaporization when it hits something on its path. Since Deep Impact was such a success, they figured that smashing old spacecraft was a good way to "recycle" them and rest assured that the space demolition derby is not about to end.

Another good point about smashing stuff is that is sounds cool. Just look at the comments here on/., people love to smash stuff. The science is hard to understand for the average tax payer but the impact isn't and Nasa is really outreach oriented. Next week a lot of people will talk about the recent smash at work, many more than those who talk about the holy quest from dark matter. Some of those will feel nostalgic and bring their kids star gazing and a new generation of astronomers will be on its way. Missions that are easy to understand keep the public interest high. One smash a year keeps the budget cut away?

On a deeper philosophical ground I realize now that hackers should learn from this effort to present to the public an over simplistic view of what you do. Most of us can't explain to our parents what we do. This is because we try to stay accurate and I think that this is wrong. No one will start coding based on just your job description so a little inaccuracy should be allowed. As Kim Binsted told us, we should always have an elevator pitch version of what we do that anyone can understand; thats how you build contacts and how budgets are allocated.

Back to smashing stuff, I think that this is the best way we have to quickly respond to opportunities: a close-by asteroid, an unexpected comet, an alien spaceship,... and we should build all new spacecrafts to be usefull when we smash them when they run out of fuel. To be usefull all the material should have its emission lines outside of Earth transparency window or at least outsides of windows for interesting stuff like organics. We should of course also launch a bunch of impactors will the sole goal of being smashed.

By the way did you know that they are studying comets and asteroids as the putative primary vector of water and amino acids to Earth? Contrary to the Miller theory, the young earth might not have been such an efficient amino acids synthesizer. On the otherhand we keep finding those in carbonacous meteorites. We have an observation that the formation of chucks of rocks in space for an unknown reason creates the building blocks for life as a byproduct. Don't you think that we should smash a lot more stuff to learn more about it? I do, let the space demolition derby go on!

Actually, if it was a renault, it was probably constructed in such a way that least damage was done to both the contents of the probe and the moon (does no-one think of the moon!). Otherwise renault wouldn't have gotten their high NCAP crash ratings [renaultusa.com] (high on pedestrian protection as well, compare that with your average hummer). Very funny ad they made about it: http://www.youtube.com/watch?v=oleDUyU4DC4 [youtube.com]

I am so proud of the Scientists who envisioned this experiment but I have to ask,Why didn't you just go to the moon and set up a base to study this stuff? I mean we have a space station, Why not a moonbase? Crash land a satellite and study the
wreck and and resulting plume for what? I gotta say that we sure are standing on our dicks with this whole moon business,
we should have been colonizing it already.

Of course NASA can barely get a mission of the ground without something exploding on or falling off of the space shuttle and Russia is in the middle of an authoritarian boondoggle and is spending most of its time flying celebrities into space. But hey, who's counting?

Of course NASA can barely get a mission of the ground without something exploding on or falling off of the space shuttle and Russia is in the middle of an authoritarian boondoggle and is spending most of its time flying celebrities into space.

That's why I'm glad the Europeans are helping to pick up the slack. I just had a hard time seeing crashing into the moon as a significant acomplishment as some stories,e.g. BBC seemed to make it out to be. Europe is the equal of the U.S. and Russia in overall te

Maybe you don't know it, but crashing onto the moon was just 1 out of 3 of SMART-1's missions [wikipedia.org]. And maybe, just maybe, North Americans will be interested in the maps SMART-1 made of the moon...